This invention pertains to catalysts for polymerizing or copolymerizing olefinic compounds and especially ethylene and other 1-olefins having a total of 2 to 8 carbon atoms and the copolymerization of these with 1-olefins containing from 2 to 20 carbon atoms, to methods of preparing the catalysts and to methods of making these polymers and copolymers.
The most pertinent prior art of which applicants are aware are the following: Z Electrochemie Vol. 63, No. 1 (59), pp. 105-111 which discloses a catalyst formed by the reaction of organoaluminum compounds and transition metal complexes and specifically organo-aluminum with the chromium acetylacetonate complex. The olefin polymerization activity of this catalyst, however, is somewhat low. U.S. Pat. Nos. 3,351,623 and 3,635,840 disclose catalysts comprising a mixture of which one ingredient is a vanadium 2,4-diketone chelate rather than the chromium chelate of this invention. The catalyst systems of this prior art and the results achieved are different from the invention here.